Compounds of the androstane and pregnane series and methods of producing the same



Patented Aug. 22, 1939 PATENT OFFICE coMPoUNns or me PBEGNANE scams AND ROSTANE AND METHODS OF PRODUCING THE SAME Adolf Butenandt, Berlln-Lichterlelde, and Willy Logemann, Berlln-Gharlottenbur Germany, assignors to Schering Aktiengesellschaft, a corporation of Germany No Drawing. Application December 5, 1936, Se-

rial No. 114,334. In Germany December I,

Claims.

This invention relates to compounds of the androstane and pregnane series and methods of producing the same.

One feature of the present invention concerns a process which allows of the conversion'of unsaturated compounds of the androstane and pregnane series which contain a methylene group in the double bond, into derivatives richer in oxygen, in which the methylene group is replaced by a keto group.

By compounds of the androst'ane and pregnane series, as employed in this specification and in the appended claims, are meant the saturated and unsaturated keto and hydroxy compounds and compounds having substituents, like acid and ether and other groups, which can be replaced by the hydroxy group, which compounds are'derived or are derivable from the hydrocarbons androstane and pregnane having the formulae CH: CH: CH:

position adjacent to the carbon to carbon free alcohols or ketones, or suitably and with the production oi better yields in the form of their corresponding derivatives; the reaction products obtained in the form of their derivatives can then be converted if desired according to known methods by hydrolysis and the like into the fundamental free compounds. When a starting material is employed which contains hydroxyl groups, and it is desired that the originally present hydroxyl groups remain unchanged in the oxidation product, it is advantageous to convert these hydroxyl groups for protection from the action of the oxidising agent by esterification, etherification, halogenation or the like into groups which by hydrolysis or the like can. be reconverted into a-hydroxyl group.

For the oxidation treatment in this process all such-agents can be employed as are capable of converting a methylene group in the position adjacent to a carbon to carbondouble bond into a keto group; to these belong, for example, compounds of hexavalent chromium such as chromium trioxide and the like and further selenium dioxide and others; in the latter case the process is advantageously conducted in the presence of catalysts such as iodine and the like. The oxidising agents are suitably employed in large ex- The products produced in this oxidation process are worked up suitably in such a manner that at first the likewise produced acid portions are separated *in' known manner from the neutral portions and "thereupon from the latter the desired "oxidation products isolated according to known{ physical or chemical methods. There is employed for this purpose. for example, in!!! may be illustrated in greater detail by means of the following formulas relating to dehydro-androsterone:

C Ha

derivatives in which R indicates O-scyl, 043ilryl, halogen or the like stsrons derivatives By the above process there are produced in particular such derivatives richer in oxygen of unsaturated compounds of the androstane and pregnane series as contain at least 3 omen atoms directly connected to the carbon atoms oi the androstane or pregnane system and as contain in the position adjacent to the carbon-carbon double bond a keto group,

According to a further feature of the present invention reduction products are produced at these specified unsaturated derivatives containing keto groups of compounds of the andro'stane andpregnane series, as are obtainable, for example,. according to the above process or by other methods.

As starting materials for this second process come into consideration, for example, the 'Z-oxoand 7-hydrom-androstenolones, the 7-oxoand 7-hydroxy-androstendione and also the diflerent isomeric 7=oxoand. 7-hydroxy-androstendlols, the corresponding unsaturated 'l-oxoand 7- hydroxy-pregnane compounds, their derivatives and similar substances. There can also be employed as starting materials, however, the corresponding saturated compounds such as the 7- oxoand 'I-hydroxy-androstanolones, 'l-oxoand 7-hydroxy-androstandiones, 'l-oxoand 'l-hydroxy-pregnanolones and the like and also their derivatives. Instead oi the 7-oxoor 7-hydro compounds mentioned the corresponding 8oxoor G-hydroxy-compounds, for instance, may likewise be used as starting materials.

For the manufacture of reduction products oi these substances it is possible to proceed in the following manner:

It, for example, only the keto groups present in the starting material are required to be reduced and the carbon-carbon double bond to remain imaltered, then suitably a reducing agent is employed 0! the type 01 aluminium isopropylate or the substance to be reduced is treated, for example, with such Grignard compounds as incline to the formation of unsaturated hydrocarbons, for example, with isopropyl magnesium halogenide and the like.

Ii on the other hand the carbon-carbon double bond oi the unsaturated starting material containing keto groups is to be hydrogenated, then suitably there is selected as hydrogenating catalyst a noble metal catalyst such as platinum, platinum oxide, palladium or nickel or an alloy skeleton catalyst of the lyst and the like.

In the present case in which there is concerned ype 01' the Raney catain the reduction among others the hydrogenation In the cases in which a hydrogenation of the carbon-carbon double bond takes place there can further also occur a reduction of any keto groups present. a

In the application of catalytic methods there are of influence on the reduction product obtainable in any particular case in addition to the type of the catalyst itself and the method of manufacture thereof, the temperature employed in the hydrogenation, the quantity of hydrogen, the pressure of the hydrogen, the duration of the treatment and the solvent employed in the hydrogenation; in this connection see, for example, the remarks in Houben-WeYl, Methoden der crganischen Chemie, vol. 2, second edition, 1933,

page373, et seq. The conditions suitable for the desired course of the hydrogenation can accordingly easily be established by corresponding experiments. The various reduction pomibilities'may be i1- hlstrated in more detail by the following formulas employing as an example the 7-010- androstendiol:

CH: CH:

OHH

HO OH H n 'I-laydroxy-androstendiol HO OH I 7-hydroxy-mdmstandiol According to a still further feature of this invention, in compounds such as, for example, those which can be obtained according to the above processes, insofar as they contain at least one hydroxyl group, a carbon-carbon double bond can be introduced when they are subjected to the action of agents splitting of! water. For this purpose are suitable the known water. splitting agents such as are described, for example, in Houben-Weyl, Methoden der organischen Chemie, vol. 2, second edition, page 744 et seq., 1922. In this way double bonds can be introduced between the 2 and 3, 6 and 7,16 and 1'1, V

and 1'7 and 13 carbons.

Instead of the compounds containing free hydroxyl groups there can be employed with advantage as starting materials also their inorganic or organic estersand these subjected to the action of acid splitting agents. In the cases,

in which the hydroxyl group to be split off is esterified by halogen hydride, there can be employed for the purpose of splitting of! of hydrohalic acid alkaline agents such as pyridine, quinoline and the like.

As starting material comes into consideration, for example, A -androstentril-3,7,17, which can be obtained in any suitable manner, for example, by reduction of M-Z-oxo-androstendlol-3.l'7,

as described above.

Instead of the free alcohol there can also be employed with particular advantage its ester, as, for example, the corresponding tribenzoate, as starting materials; there is then obtained by the process according to the invention with splitting oil? of 1 mol of acid the corresponding doubly unsaturated diester, from which the A -A -androstandiendiol-3.17 can be obtained by hydrolysis.

By employing as starting material for the present process a A -7-oxo-androstendiol-3.1'7 or its diaeetate as can be obtained, for example, as described above, there is obtained according to this process a A -A -androstandienol-l'l-one-7.

The process of this feature of the invention may be illustrated by means of the following formulas: in these formulae x indicates a hydroxyl group or an acid radical:

A -7-oxo-androstendiol-compound M-AHndrostandienol-U-one-Z The following examples serve to illustrate the invention without, however, limiting the same to them:

Example 11 5.5 grams of androstendiol diacetate produced from androstendiol by aeetylation are dissolved in 70 ccs. of glacial acetic acid and heated to 55 C. Then with stirring a solution of 4 grams of chromium trioxide in 2.5 ccs. of water and 2.5 ccs. of glacial acetic acid is'allowed to drop in within two hours. Finally, the whole is heated for 2 hours further to about 50-55 C. The chromic acidhas after this time been practically completely consumed. The remainder is destroyed by the addition of a few ccs. of methyl alcohol at lo-50 C. 'I'he reaction solution is, poured into 600 ccs. of water and extracted twice each time with 500 cos. of benzene. The benzene Till) rated with N-caustic soda lye into an acid and neutral portion. The benzene layer. which contains the neutral portion, is washed with water and dried with magnesium sulphate. Alter the evaporation of the e there remains a resi= due which is recrys irom methanol. 1.6 grams of M-l-oxo-androstendiol dlacetate-3.l'l of M. P. mil-220 C. are w? From the mother liquor can be isolated products still more rich in oxygen.

500 mg. of o -l-oxo-endrostendiol diacetote- 3.17 are for the purpose of saponlfication dissolved in 50 cos. of 2 N sodi methylate solu tion and heated for minutes to weak boiling; then the reaction solution is diluted with water and extracted with ether in the customary manner. The residue remaining after the evaporation of the other is recrystallized from acetonepetrol ether. There is thus obtained the A -loxo-androstendiol-3l? from alcohol in ps oi melting point 201 C. e optical rotation amounts to -132.8 (in alcohol); the an of the absorption is at 238,...

Instead of the androstendiol diacetate there can be employed for the omdation also other androstendiol diesters, for example, the androstendiol dibenzoate or androstendiol acetate benzoate or the like. Also the esters of androstenolones or pregnenolones can be oxidised in an analogous manner.

Example 2 0.4 gram of androstendiol monoacetate oi M. P. 142-143 C. is suspended in 20 cos. of glacial acetic acid, treated with a solution of 0.46 gram of chromium trioxide in a. trace of. water and violently shaken for 10 hours. The reaction solution initially becomes somewhat heated and the starting material passes gradually into solution. After a further 12 hours standing the solution is treated with 200 cos. of water and extracted three times with ether. The ether extract is washed with water and sodium carbonate solution and after drying over sodium sulphate evaporated. The yellow colored solid residue from the ethereal solution is sublimed at 130-140 C. in a high vacuum and recrystallised from alcohol to a constant melting point of 198-201 C. Yield 83.7 mg.=20.2% oi the theory.

The product obtained corresponds to the 6- oxo-testosterone acetate.

For the purpose of saponiiloation oi the 8-oxotestosterone acetate to the tree alcohol a 0.1% solution of the acetate in 0.1% anhydrous methyl alcoholic hydrochloric acid-.is heated to boiling for 2, hours on the water bath, considerably concentrated in vacuum, treated with water and extracted with other. After the evaporatio 01' the ether there remains a red colored oil-which is purified by sublimation in high vacuum at 140-150 C. and by recrystallisation trouncetone-ether; long white needles- .o! .M. P. zoo-205 c. g [a 58 in acetone).

Yield-t from 51.6 mg. or acetate 18.4 mg.- of -6 oxo-testosterone are obtained (40% of "the ory).----- Thefi-oxo-testosterone' also be obtained without high vacnum dist-auctiont nthe =ye1- low residue from the ethereal solution is dissolved in 05% alcohol and allowed to stand for some time there is obtained a white flooculent precipitate which can be removed by filtration; after concentration of the alcoholic solution the fi-oxo-testostcrone orystallises in yellow prisms,

and alter iurther concentration there separates a mixture 01' yellow prisms and white needles. By extraction of this mixture of substances with a little other, the white needles which are easily soluble in. other can be separated from the yellow prisms. The two fractions which orystallise of a yellow color are combined; they consist of fi-oxo-testosterone and can be purified by recrysttion from alcohol. The residue of the ether extract by repeated crystallisation from alcohol yields the white needles in pure form; they melt at 229-231 C. but only become completely liquid at 239-24130.

[a]i= 29.9 :I: l.3 (in acetone).

Example 3 1.4 grams of chromium trioxide are dissolved in a trace oi water and added to a solution or 1 gram of dehydro androsterone in cos. oi glacial acetic acid. The reaction solution is shaken over night then diluted with water and extracted with ether. The ethereal solution, after washing with sodium carbonate solution and water, is dried over sodium sulphate and evaporated; the yellow colored residue is recrystallised several times from alcohol; from the mostly yellow crystallisate a small quantity'of a compound crystallisingin white rosettes can be dissolved out. The yellow prisms (androstentrionel melt at 216-217 C. and exhibit a rotation [oil= +42.l'1.4 (in acetone).

Yield about 25%. Its oxime is obtained in the iollowinginannerz 21.6 mg. of androstentrione, mg. of hydroxylamine hydrochloride and 100 mg. of sodium acetate are dissolved in about 80% alcohol and-heated under reflux for 4 hours. The reaction solution is treated with water and extracted with ether; the portions soluble in ether separate from dilute alcohol in an amorphous condition; they are obtained crystalline from ether-and petrol ether but do not exhibit a sharp melting point butt-sinter at 188 C. and decompose gradually at 235-237 C. at which 310:2: complete melting with decomposition takes '.In an oxidation 012 grams of dehydro androsterone by the above described method 38.8 mg. of the white crystallisate were separated from the yellow androstentrione. The latter can also be dissolved out from the mixture of the two substances by extraction with benzene. The white substance forms beautiful prismatic needles (from alcohol), which at 225 C. become discolo'red and at 248-249 C. melt. The mixed meltins. point with'androstentrione (216-217 C.) is 297-5309- CJ 4 [a]'=+54.6 (in acetone).

The white vacuum at 165 C. with decomposition; they are stable to 1 hour boiling with acetic anhydride and inall probability constitute an andro'stantrione- (8.8.1'l-)-ol-5.-

orystalscan be distilled in ahigh full oestrus reaction.

Example 4 1.1 grams of 'T-oxo-androstendiol diacetate are treated with 3 grams of distilled, aluminium. isopropylate and 50 ccs. of absolute isopropyl alcohol. The whole is heated to boiling for '7 hours, a further 50 cos. isopropyl alcohol being added after about 4 hours of the heating. and then about 60 cos. are distilled oil with the aid of a Hahnsch apparatus. In the distillate alter the addition of hydroxylamine hydrochloride the acetone produced can be determined with N/ caustic soda lye and accordingly the reduction yield. The flask residue is diluted with ice water and allowed to stand for a long time; then dilute sulphuric acid is added and the whole diluted with water. Thereupon the separated precipitate is filtered oflf and after drying in benzene is dissolved with the addition of some methanol. The whole is filtered, the solution somewhat evaporated and allowed to crystallise. Thereis thusobtained the 7-hydroxy-androstendiol diacetate, which exhibits a melting point of 241- 242" C.; by saponification the free trialcohol can be obtained therefrom.

Example 5 Example 6 200 mg. of 'I-oiro-androstendlol diacetate are shaken with 0.5 gram of previously reduced platinum oxide catalyst in 40 cos. of glacial acetic acid in a shaking vessel with hydrogen until 2 mol of hydrogen are taken up. The liquid is filtered from platinum, the filtrate poured into water and extracted with ether. The ethereal solution is washed with N-caustic soda lye and finally with water. The ether is dried with magnesium sulphate and evaporated. The residue is crystallised from dilute. alcohol. There is obtained in this manner the 7-hydroxy-androstandiol diacetate and therefrom by saponification with N-methyi alcoholic caustic 'pptash lye the '7-hydroxy-androstandiol.

Example 7 880 mg. of A 1 7-oxoandrostendioldiacetate- 3.17 are dissolved in 30 cos. of absolute isopropyl alcohol. To the hot solution are added about 3 grams of freshly distilled aluminium isopropylate, then the reaction mixture is heated to boiling for 24 hours on a water bath with descending condenser with the exclusion of moisture. After addition of 10 cos. of 2N methylalcoholic caustic potash lye the solution is allowed to stand in the hot tor a further minutes and then the reaction solution is treated with water and dilute hydrochloric acid and extracted with ether.

From the ethereal solution there are obtained after the distillation of the ether 820 mg. of an oil. This oil is dissolved in 3 cos. of pyridine and treated with 2 cos. of benzoyl chloride. After the solution has been allowed to stand for 24 hours an excess of N-sulphuric acid is introduced.

The oil which thereby separates, after pouring oil the water, is well worked up with alcohol. After repeated precipitation of the product from acetone with alcohol there is obtained the A -androstentriol tribenzoate-3.7.17 from acetone in felted needles of melting point 250-251 0.; it exhibits with sulphuric acid a characteristic deep red color. I

Example 8 500 mg. of A-androstentrioltribenzoate-3.7.1'7

are subiected to vacuum distillation; thereby benzoic acid splits oil. The distillate obtained on further temperature increase exhibits after recrystallisation from alcohol a melting point of 2l1-213 C. and gives on melting with chloral hydrate a deep blue coloration.

'E'mmple 9 200 mg. of A-'7-oxo-androstendiol-3.17-diacetate are heated for 20 minutes to boiling with 15 cos. of Z-N-methyl alcoholic caustic potash lye, the reaction solution is thereupon diluted with water and iworked up in the customary manner. After recrystallisation from dilute alcohol the A -A'-andr0standieno1-17-one-7 crystallises in small plates of melting point I'll-172 C.

The optical rotation amounts to law: about -375 (in alcohol).

The absorption spectrum exhibits a maximum at 280 The product yields lises from alcohol in needles Oi course, various other modifications in the procedure of the process of the present invention may be resorted to within the scope of the appended claims without departing from the principies set forth herein.

The products obtainable according to the present invention constitute from a therapeutic point of view valuable substances; they either themselves possoss Physiological activity or serve for further working up to physiologically active coman acetate which crystalof melting point group, are subjected to the action of oxidizing agents capable of converting such methylene group into a carbonyl group without protection of the double bond.

2. Process as claimed in claim 1 in which dehydroandrosterone is employed as starting material.

3. Process as claimed in claim 1 in which an oxygen-containing oxidizing compound of hexavalent chromium is employed as oxidizing agent.

4. Process as claimed in claim 1 in which the starting material contains a hydroxyl group which is protected from the action of the oxidizing agent by conversion into such a group as by hydrolysis can again be converted into a hywhich is protected from the action of the osidizing agent by conversion into such a group as by hydrolysis can again be converted into a hydroxylf group and in which the reaction product is sub"-- sequently hydrolyzed to restore the hydrox'yl group.

6. Process as claimed in claim 1 in whichdehydroandrosteroue is employed as the starting material and an oxygen-liberating hexavalent chromium compound as the oxidizing agent.

7. Process for the manufacture of reduction products of derivatives richer in oxygen of com pounds of the androstane and pregnane series wherein reducible derivatives richer in oxygen of compounds of the androstane and pregnane series as contain at least 3 oimgen atoms directly, connected to the carbon atoms of the androstane or pregnane system are subjected to the action of reducing agents. a

8. Process as claimed in claim '7 in which a. member of the group consisting of 'I-oxoand '7-hydroxy-androstendiones is employed as starting material.

9. Process as claimed in claim7, wherein the reducing agent is a compound which is itself 88w. pable of giving off hydrogen.

10. Process as claimed in claim "I, wherein the reducing agent is aluminium isopropylate.

11. Process as claimed in claim 7 in which .the reducing agent is catalytically activated hydrogen in the presence of a noble metal catalyst.

12. Process for the manufacture of-derlvatlves richer in oxygen of unsaturated compounds of the androstane and pregnane series, wherein unsaturated compounds of the androstane and pregnane series, which possess in a position adJacen't to the carbon-to-carbon double bond a methylene group, are subjected to the action of oxidising agents capable of converting such methylene group into a carbonyl group without protection of the double bond and are subsequently subjected to the action of a reducing agent. I

13. Process for the manuiacture or unsaturated derivatives of the androstane and pregnane' se? ries, comprising subjecting a compound oi said series having attached to the nucleus a. substituent of the class consisting of oxygen, th'hydroxy group and groups which on hydrolysis can be replaced by hydroxyl, to the action of an agent capable of splitting oi! said substituent together with hydrogen while'leavfng the cyclopentano phenanthrene skeleton intact.

14. Process as claimed in claim 13 in which the splitting off of the'said substituent together with hydrogen is carried out by heating to elevated temperatures.

15. Process as claimed in claim 13, wherein reaction products having a substituted hydroxyl group are hydrolyzed to restorethe hydroxyl group.

16. Process for the manufacture oi unsaturated derivatives of the androstane and pregnane series which comprises subjecting an unsaturated compound oi. the andrcstane and pregnane series having a methylene group in a position adjacent to a carbon-to-carbon double bond to the action of an oxidizing agent without protection of the double bond to introduce an oxygen atom into the molecule, andsubsequently subjecting the reaction product to the action oi. an agent capable oi splitting off hydrogen and another substituent while leaving the cyclopentano phenanthrene skeleton intact.

1'7. Process as claimed in claim 18, wherein any hydroxyl groups in the starting material are first converted into groups which on hydrolysis can be replaced by a hydroxyl group, and wherein the reaction product is' subsequently hydrolyzed to restore the hydroxyl group.

18. Process for the manufacture oi unsaturated derivatives of the androstane and pregnane series which comprises subjecting a keto compound of the androstane and pregnane series having at least two additional oxygen atoms connected directly to the carbon skeleton characteristic of its series, said compound including a substituent of the group consisting of ester, ether and halogen groups, to the action of a reducing agent, and subsequently subjecting the reaction product to the action of anagent capable of splitting ofl hydrogen and said substituent to introduce a double bond into the compound while leaving the cyclo-' pentano phenanthrene skeleton intact.

19. Unsaturated compounds of the androstane and pregnane series or the general formula.

CmHuXYZ wherein X is located at the carbon atom 17 and stands for a member of the group consisting of oxygen,

, and

mdmmo whereas Y is located at the carbon atom 3 and represents a member of the group consisting of oxygen and R HzC.OC Bic-(REC and H n I n whereas Y is located at the carbon atom 3 and represents a member of the group consisting of oxygen and while Z is located at the carbon atoms or '7 and I stands for .a member of the group consisting of oxygen and R indicating a member of the group consisting of the hydroxyl group and groups that, upon hydrolysis, can be converted into the hydroxyl group, the carbon-to-carbon double bond when present being located between the carbon atoms 4' and 5 or 5 and 6.

21. Unsaturated compounds of the androstane and pregnane series of the general formula CuHmXY wherein m means 24 or 2'6 and X is oxygen and R indicating a member of the group consisting .of the hydroxyl group and'groups that, upon hydrolysis, can be converted into the hydroxyl 15 group, a carbon-to-carbon double bond being located between the carbon atoms 6 and 7 or '1" and 8.

22. Unsaturated compounds of the androstane and pregnane series 01' the. general formula C19HmXZ wherein m means 24 or 26 and X is located at the carbon atom 17 and stands for a-member of the group consisting of oxygen,

R 1110.00 momma and whereas Z is located at the carbon atom 6 or '7 and stands for a member of the group consisting of oxygen and a 80 R B group, R indicating a member of the class consisting of the hydroxyl group and groups that, 3 upon hydrolysis. can be converted into the hyagents capable droxyl roup. a earbon-to-carbon double bond being located between the carbon atoms 2 and 3 or 3 and 4.

23. Process for the manufacture'ot derivatives richerin oxygen of unsaturated compounds of the androstane and pregnane series, wherein unsaturated compounds of the androstane and preg- ,nane series, which possess ina position adjacent to the carbon-to-carbon double bond a methylene group, are subjected to the action of oxidising of converting such methylene group into a carbonyl group without protection of the double bond, the reaction product being then treated with-a reducing agent and being subsequently subjected to the action of an agent capable of splitting 01! hydrogen and anothersubstituent to introduce a double bond into the rnblecule.

24 An unsaturated compound or the androstane and pregnane series having a ketonic group between the 5- and 8- carbons.

25. A compound of the androstane and pregnane series' having at a-carbon atom, between i the 5- and 8- carbons, a substituting group of the class consisting of oxygen and mom nu'rammnm wnlmr LOGEMANN. 

